Sulphur dioxide is never added to grapes during processing for sparkling wine as this would increase phenolic extraction. There is no crushing or de-stemming of the grapes. The grape bunches must be loaded into the press whole in order to have low solids and phenolics and allow for the fractionated extraction of the juice.

The very first juice from the press (known as autorun) is often separated as it may contain water, dirt and pesticides. In Champagne, the juice from a 4 tonne press is separated into the following:

• Cuvée, first 512 l/tonne
• 1° Taille, next 102 l/tonne
• 2° Taille, next 51 l/tonne

These are kept separate until blending. If any other juice is extracted, it should not be used in Champagne. The Cuvée juice is regarded as the highest quality, as it is derived from the intermediate zone of the berry, which is high in sugars and acids, and very low in colour & phenolics.

Horizontal screw presses are also used, but the chains and hoops should be removed.